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<h1>examples/OpenCV/watershed/watershed.cpp</h1><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment">This source is one of the sample codes from the OpenCV 2.1 library</span>
<a name="l00003"></a>00003 <span class="comment">*/</span>
<a name="l00004"></a>00004 
<a name="l00005"></a>00005 <span class="preprocessor">#ifdef _CH_</span>
<a name="l00006"></a>00006 <span class="preprocessor"></span><span class="preprocessor">#pragma package &lt;opencv&gt;</span>
<a name="l00007"></a>00007 <span class="preprocessor"></span><span class="preprocessor">#endif</span>
<a name="l00008"></a>00008 <span class="preprocessor"></span>
<a name="l00009"></a>00009 <span class="preprocessor">#define CV_NO_BACKWARD_COMPATIBILITY</span>
<a name="l00010"></a>00010 <span class="preprocessor"></span>
<a name="l00011"></a>00011 <span class="preprocessor">#ifndef _EiC</span>
<a name="l00012"></a>00012 <span class="preprocessor"></span>
<a name="l00013"></a>00013 <span class="comment">/* This is a standalone program. Pass an image name as a first parameter of the program.</span>
<a name="l00014"></a>00014 <span class="comment">   Switch between standard and probabilistic Hough transform by changing &quot;#if 1&quot; to &quot;#if 0&quot; and back */</span>
<a name="l00015"></a>00015 <span class="preprocessor">#include &lt;opencv/cv.h&gt;</span>
<a name="l00016"></a>00016 <span class="preprocessor">#include &lt;opencv/highgui.h&gt;</span>
<a name="l00017"></a>00017 
<a name="l00018"></a>00018 
<a name="l00019"></a>00019 <span class="preprocessor">#include &lt;stdio.h&gt;</span>
<a name="l00020"></a>00020 <span class="preprocessor">#include &lt;stdlib.h&gt;</span>
<a name="l00021"></a>00021 <span class="preprocessor">#endif</span>
<a name="l00022"></a>00022 <span class="preprocessor"></span>
<a name="l00023"></a>00023 IplImage* marker_mask = 0;
<a name="l00024"></a>00024 IplImage* markers = 0;
<a name="l00025"></a>00025 IplImage* img0 = 0, *img = 0, *img_gray = 0, *wshed = 0;
<a name="l00026"></a>00026 CvPoint prev_pt = {-1,-1};
<a name="l00027"></a>00027 
<a name="l00028"></a>00028 <span class="keywordtype">void</span> on_mouse( <span class="keywordtype">int</span> event, <span class="keywordtype">int</span> x, <span class="keywordtype">int</span> y, <span class="keywordtype">int</span> flags, <span class="keywordtype">void</span>* param )
<a name="l00029"></a>00029 {
<a name="l00030"></a>00030     <span class="keywordflow">if</span>( !img )
<a name="l00031"></a>00031         <span class="keywordflow">return</span>;
<a name="l00032"></a>00032 
<a name="l00033"></a>00033     <span class="keywordflow">if</span>( event == CV_EVENT_LBUTTONUP || !(flags &amp; CV_EVENT_FLAG_LBUTTON) )
<a name="l00034"></a>00034         prev_pt = cvPoint(-1,-1);
<a name="l00035"></a>00035     <span class="keywordflow">else</span> <span class="keywordflow">if</span>( event == CV_EVENT_LBUTTONDOWN )
<a name="l00036"></a>00036         prev_pt = cvPoint(x,y);
<a name="l00037"></a>00037     <span class="keywordflow">else</span> <span class="keywordflow">if</span>( event == CV_EVENT_MOUSEMOVE &amp;&amp; (flags &amp; CV_EVENT_FLAG_LBUTTON) )
<a name="l00038"></a>00038     {
<a name="l00039"></a>00039         CvPoint pt = cvPoint(x,y);
<a name="l00040"></a>00040         <span class="keywordflow">if</span>( prev_pt.x &lt; 0 )
<a name="l00041"></a>00041             prev_pt = pt;
<a name="l00042"></a>00042         cvLine( marker_mask, prev_pt, pt, cvScalarAll(255), 5, 8, 0 );
<a name="l00043"></a>00043         cvLine( img, prev_pt, pt, cvScalarAll(255), 5, 8, 0 );
<a name="l00044"></a>00044         prev_pt = pt;
<a name="l00045"></a>00045         cvShowImage( <span class="stringliteral">&quot;image&quot;</span>, img );
<a name="l00046"></a>00046     }
<a name="l00047"></a>00047 }
<a name="l00048"></a>00048 
<a name="l00049"></a>00049 
<a name="l00050"></a>00050 <span class="keywordtype">int</span> main( <span class="keywordtype">int</span> argc, <span class="keywordtype">char</span>** argv )
<a name="l00051"></a>00051 {
<a name="l00052"></a>00052     <span class="keywordtype">char</span>* filename = argc &gt;= 2 ? argv[1] : (<span class="keywordtype">char</span>*)<span class="stringliteral">&quot;fruits.jpg&quot;</span>;
<a name="l00053"></a>00053     CvMemStorage* storage = cvCreateMemStorage(0);
<a name="l00054"></a>00054     CvRNG rng = cvRNG(-1);
<a name="l00055"></a>00055 
<a name="l00056"></a>00056     <span class="keywordflow">if</span>( (img0 = cvLoadImage(filename,1)) == 0 )
<a name="l00057"></a>00057         <span class="keywordflow">return</span> 0;
<a name="l00058"></a>00058 
<a name="l00059"></a>00059     printf( <span class="stringliteral">&quot;Hot keys: \n&quot;</span>
<a name="l00060"></a>00060             <span class="stringliteral">&quot;\tESC - quit the program\n&quot;</span>
<a name="l00061"></a>00061             <span class="stringliteral">&quot;\tr - restore the original image\n&quot;</span>
<a name="l00062"></a>00062             <span class="stringliteral">&quot;\tw or SPACE - run watershed algorithm\n&quot;</span>
<a name="l00063"></a>00063             <span class="stringliteral">&quot;\t\t(before running it, roughly mark the areas on the image)\n&quot;</span>
<a name="l00064"></a>00064             <span class="stringliteral">&quot;\t  (before that, roughly outline several markers on the image)\n&quot;</span> );
<a name="l00065"></a>00065 
<a name="l00066"></a>00066     cvNamedWindow( <span class="stringliteral">&quot;image&quot;</span>, 1 );
<a name="l00067"></a>00067     cvNamedWindow( <span class="stringliteral">&quot;watershed transform&quot;</span>, 1 );
<a name="l00068"></a>00068 
<a name="l00069"></a>00069     img = cvCloneImage( img0 );
<a name="l00070"></a>00070     img_gray = cvCloneImage( img0 );
<a name="l00071"></a>00071     wshed = cvCloneImage( img0 );
<a name="l00072"></a>00072     marker_mask = cvCreateImage( cvGetSize(img), 8, 1 );
<a name="l00073"></a>00073     markers = cvCreateImage( cvGetSize(img), IPL_DEPTH_32S, 1 );
<a name="l00074"></a>00074     cvCvtColor( img, marker_mask, CV_BGR2GRAY );
<a name="l00075"></a>00075     cvCvtColor( marker_mask, img_gray, CV_GRAY2BGR );
<a name="l00076"></a>00076 
<a name="l00077"></a>00077     cvZero( marker_mask );
<a name="l00078"></a>00078     cvZero( wshed );
<a name="l00079"></a>00079     cvShowImage( <span class="stringliteral">&quot;image&quot;</span>, img );
<a name="l00080"></a>00080     cvShowImage( <span class="stringliteral">&quot;watershed transform&quot;</span>, wshed );
<a name="l00081"></a>00081     cvSetMouseCallback( <span class="stringliteral">&quot;image&quot;</span>, on_mouse, 0 );
<a name="l00082"></a>00082 
<a name="l00083"></a>00083     <span class="keywordflow">for</span>(;;)
<a name="l00084"></a>00084     {
<a name="l00085"></a>00085         <span class="keywordtype">int</span> c = cvWaitKey(0);
<a name="l00086"></a>00086 
<a name="l00087"></a>00087         <span class="keywordflow">if</span>( (<span class="keywordtype">char</span>)c == 27 )
<a name="l00088"></a>00088             <span class="keywordflow">break</span>;
<a name="l00089"></a>00089 
<a name="l00090"></a>00090         <span class="keywordflow">if</span>( (<span class="keywordtype">char</span>)c == <span class="charliteral">&#39;r&#39;</span> )
<a name="l00091"></a>00091         {
<a name="l00092"></a>00092             cvZero( marker_mask );
<a name="l00093"></a>00093             cvCopy( img0, img );
<a name="l00094"></a>00094             cvShowImage( <span class="stringliteral">&quot;image&quot;</span>, img );
<a name="l00095"></a>00095         }
<a name="l00096"></a>00096 
<a name="l00097"></a>00097         <span class="keywordflow">if</span>( (<span class="keywordtype">char</span>)c == <span class="charliteral">&#39;w&#39;</span> || (<span class="keywordtype">char</span>)c == <span class="charliteral">&#39; &#39;</span> )
<a name="l00098"></a>00098         {
<a name="l00099"></a>00099             CvSeq* contours = 0;
<a name="l00100"></a>00100             CvMat* color_tab = 0;
<a name="l00101"></a>00101             <span class="keywordtype">int</span> i, j, comp_count = 0;
<a name="l00102"></a>00102 
<a name="l00103"></a>00103             cvClearMemStorage(storage);
<a name="l00104"></a>00104 
<a name="l00105"></a>00105             <span class="comment">//cvSaveImage( &quot;wshed_mask.png&quot;, marker_mask );</span>
<a name="l00106"></a>00106             <span class="comment">//marker_mask = cvLoadImage( &quot;wshed_mask.png&quot;, 0 );</span>
<a name="l00107"></a>00107             cvFindContours( marker_mask, storage, &amp;contours, <span class="keyword">sizeof</span>(CvContour),
<a name="l00108"></a>00108                             CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE );
<a name="l00109"></a>00109             cvZero( markers );
<a name="l00110"></a>00110             <span class="keywordflow">for</span>( ; contours != 0; contours = contours-&gt;h_next, comp_count++ )
<a name="l00111"></a>00111             {
<a name="l00112"></a>00112                 cvDrawContours( markers, contours, cvScalarAll(comp_count+1),
<a name="l00113"></a>00113                                 cvScalarAll(comp_count+1), -1, -1, 8, cvPoint(0,0) );
<a name="l00114"></a>00114             }
<a name="l00115"></a>00115 
<a name="l00116"></a>00116             <span class="keywordflow">if</span>( comp_count == 0 )
<a name="l00117"></a>00117                 <span class="keywordflow">continue</span>;
<a name="l00118"></a>00118 
<a name="l00119"></a>00119             color_tab = cvCreateMat( 1, comp_count, CV_8UC3 );
<a name="l00120"></a>00120             <span class="keywordflow">for</span>( i = 0; i &lt; comp_count; i++ )
<a name="l00121"></a>00121             {
<a name="l00122"></a>00122                 uchar* ptr = color_tab-&gt;data.ptr + i*3;
<a name="l00123"></a>00123                 ptr[0] = (uchar)(cvRandInt(&amp;rng)%180 + 50);
<a name="l00124"></a>00124                 ptr[1] = (uchar)(cvRandInt(&amp;rng)%180 + 50);
<a name="l00125"></a>00125                 ptr[2] = (uchar)(cvRandInt(&amp;rng)%180 + 50);
<a name="l00126"></a>00126             }
<a name="l00127"></a>00127 
<a name="l00128"></a>00128             {
<a name="l00129"></a>00129             <span class="keywordtype">double</span> t = (double)cvGetTickCount();
<a name="l00130"></a>00130             cvWatershed( img0, markers );
<a name="l00131"></a>00131             t = (double)cvGetTickCount() - t;
<a name="l00132"></a>00132             printf( <span class="stringliteral">&quot;exec time = %gms\n&quot;</span>, t/(cvGetTickFrequency()*1000.) );
<a name="l00133"></a>00133             }
<a name="l00134"></a>00134 
<a name="l00135"></a>00135             <span class="comment">// paint the watershed image</span>
<a name="l00136"></a>00136             <span class="keywordflow">for</span>( i = 0; i &lt; markers-&gt;height; i++ )
<a name="l00137"></a>00137                 <span class="keywordflow">for</span>( j = 0; j &lt; markers-&gt;width; j++ )
<a name="l00138"></a>00138                 {
<a name="l00139"></a>00139                     <span class="keywordtype">int</span> idx = CV_IMAGE_ELEM( markers, <span class="keywordtype">int</span>, i, j );
<a name="l00140"></a>00140                     uchar* dst = &amp;CV_IMAGE_ELEM( wshed, uchar, i, j*3 );
<a name="l00141"></a>00141                     <span class="keywordflow">if</span>( idx == -1 )
<a name="l00142"></a>00142                         dst[0] = dst[1] = dst[2] = (uchar)255;
<a name="l00143"></a>00143                     <span class="keywordflow">else</span> <span class="keywordflow">if</span>( idx &lt;= 0 || idx &gt; comp_count )
<a name="l00144"></a>00144                         dst[0] = dst[1] = dst[2] = (uchar)0; <span class="comment">// should not get here</span>
<a name="l00145"></a>00145                     <span class="keywordflow">else</span>
<a name="l00146"></a>00146                     {
<a name="l00147"></a>00147                         uchar* ptr = color_tab-&gt;data.ptr + (idx-1)*3;
<a name="l00148"></a>00148                         dst[0] = ptr[0]; dst[1] = ptr[1]; dst[2] = ptr[2];
<a name="l00149"></a>00149                     }
<a name="l00150"></a>00150                 }
<a name="l00151"></a>00151 
<a name="l00152"></a>00152             cvAddWeighted( wshed, 0.5, img_gray, 0.5, 0, wshed );
<a name="l00153"></a>00153             cvShowImage( <span class="stringliteral">&quot;watershed transform&quot;</span>, wshed );
<a name="l00154"></a>00154             cvReleaseMat( &amp;color_tab );
<a name="l00155"></a>00155         }
<a name="l00156"></a>00156     }
<a name="l00157"></a>00157 
<a name="l00158"></a>00158     <span class="keywordflow">return</span> 1;
<a name="l00159"></a>00159 }
<a name="l00160"></a>00160 
<a name="l00161"></a>00161 <span class="preprocessor">#ifdef _EiC</span>
<a name="l00162"></a>00162 <span class="preprocessor"></span>main(1,<span class="stringliteral">&quot;watershed.cpp&quot;</span>);
<a name="l00163"></a>00163 <span class="preprocessor">#endif</span>
</pre></div></div>
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<center><a href="http://perception.inf.um.es/QVision">QVision framework</a>.
<a href="http://perception.inf.um.es">PARP research group</a>.
Copyright &copy; 2007, 2008, 2009, 2010, 2011.</center>
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